1. Technical Field
The disclosure relates to a frequency divider, and more particularly, to an injection-locked frequency divider (ILFD).
2. Related Art
Frequency divider plays a role in a phase-locked loop (PLL), and is also a critical circuit in a wireless communication system. The maximal working frequency of the PLL is generally limited by an operating frequency range of a first-stage frequency divider. However, existing frequency dividers may be generally classified into three types, namely, current mode logic (CML) frequency dividers, ILFDs, and regenerative frequency dividers.
Generally, the CML frequency divider has a good sensitivity and bandwidth, but the operating frequency is not high due to the limitation by a current gain cut-off frequency (ft) of the element. Although the working frequency of the regenerative frequency divider is higher than that of the CML frequency divider, may result in excessive consumption of direct current (DC) power. The ILFD has a low DC power consumption and high operating frequency; however, the range of injection-locking is narrower, and thus is not suitable for current wireless communication applications requiring high data transfer rate and low DC power consumption.